Last week Kristen bought 5 pounds of apples this week she bought 1 half of that amount how many pounds of apples did Kristen buy this week

Last week he bought three apples for $3.90. The cost of an apple = 3.9/3 = 1.3 This week he bought 2 more apples which totals 5 for $6.50 The cost of each apple = 6.5/5 = 1.3. The cost of an apple in the two weeks is the same. Arnold bought more apples in the following week but there was a corresponding raise in price. When he bought fewer apples last week he never had to pay as much as he did the year later

She bought 2.5 pounds of apples this week.

Explanation:

5 divided by 2 is 2.5.